Species · genus Hibiscus · Malvaceae
Bladder Ketmia
Hibiscus trionum L.
Also known as: Flower Of An Hour · Venice Mallow · Rosemallow · Modesty · Trilobate Ketmia
Cultivars of H. trionum
The named forms growers keep — each with its own page, each honest about how much we know.
No named cultivars catalogued under H. trionum yet. When growers document a stable, named form, it earns its own page here.
Guide
The species-level account. Cultivar pages build on this and say where they differ.
A Widespread Annual Mallow
Hibiscus trionum is an annual or biennial member of the mallow family, Malvaceae. It grows primarily within the subtropical biome, and its accepted scientific name was first published by Linnaeus in 1753.
Source: Kew
From Europe to the Himalaya
This species is native to a broad sweep of territory running from east-central and eastern Europe through the Mediterranean to the western Himalaya, taking in countries such as Greece, Italy, Iran, Afghanistan, and Pakistan along the way. It has since been introduced far beyond that native range, turning up as an established plant across much of North America, parts of East Asia, New Zealand, and various islands, among many other regions.
Source: Kew
An Annual or Biennial Habit
Hibiscus trionum is recorded as either an annual or a biennial, completing its life cycle within one or two growing seasons rather than persisting as a long-lived perennial. It is classed within the subtropical biome, reflecting the warmer native conditions it is adapted to.
Source: Kew
Care recipe
The species record — the baseline every cultivar inherits unless it says otherwise.
Care notes are early — not yet verified
- Light
- ai:claude-opus-4-8
- Water
- ai:claude-opus-4-8 (range 5-10d)
- Humidity
- ai:claude-opus-4-8
- Soil
- ai:claude-fable-5
- Care
- ai:claude-fable-5
Direct sun
≈ every 10 days
Medium
13–30 °C
Light, free-draining sandy potting mix
Sown from seed each season
Light balanced feed monthly while actively growing
Fast
Freely produces short-lived cream-and-maroon flowers in strong light
Not yet documented
This is where toxicity lives — every cultivar of this species inherits it and none can override it.
Reference images
Every image credited. Licenses link to their deeds.
Sources: ai:claude-opus-4-8 · ai:claude-opus-4-8 (range 5-10d) · ai:claude-fable-5
Kept true by its growers
Every fact here carries its source. Grow Bladder Ketmia yourself? What you’ve observed — how it drinks, how it holds its color, a name that’s off — and a clear photo of your plant are exactly what keep this page honest. Contributions are reviewed before anything changes.
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